Answer:
The correct anser is : lo.
Marcos lo busca.
Explanation:
To make this exercise we must find the pronoun of the direct object. The direct object is the one that goes along with the verb and is in charge of indicating to whom the action of the sentence is addressed.
That is why, the pronoun of the direct object is going to replace exactly the direct object, that is to say that it is going to replace the object of the action, in this case: el gerente (it is looked for by Marcos).
Next, I will write what these pronouns are in Spanish:
Subject Singular Plural
First person me nos
Second person te os
Third person lo, la los, las
